Roll roofing fastener



R E5 www w1 EM, O G2 my Fa OM May 21, 1935.-

Patented May 2l, 1935 UNITED STATES ROLL ROOFING FASTENER Hamilton Maze,Peru, Ill., assignor to W. H. Maze Company, Peru, Ill., a corporation ofIllinois Application May 20, 1933, Serial No. 671,957

11 Claims.

This invention relates to roll roofing, and more particularly to afastener of the nail type Which will securely hold so-called rollroofing on a roof for an extended period of time and fully meet all 5 ofthe desirable requirements of the roofing manufacturers, dealers andusers.

Recent years have seen a general advance and improvement'in the qualityof all types of roofing, and it is pretty well recognized, for example,that asphalt roll rooiings are at a high state of perfection. In fact,this is true of the whole asphalt line. The weight of felt, the processof saturation, permanency of surfacing, colors, and color harmony, haveall been receiving major amounts of attention. i

In this development, the laboratory has played an important role.Through the device of accelerated atmospheric conditions, in which air,Water, heat, cold, and even intense artificial sunlight are allfaithfully reproduced, asphalt goods can now, for the purpose oftesting, be artificially weathered in a few days time. These few daysare equivalent to years of normal out-of-door conditions. The relativemerits of any piece of roofing can be thus quickly determined. As aresult, asphalt roongsin their respective grades, have and are passingthrough tests and checking methods so rigorous that the factors makingfor their long life are known-processes of production correspondinglychangedand out of it all comes a finished product that stands high inquality, long life and uniformity.

However, the best roll roong must still be dependent 01; its fastening,and, while the roll roofing itself is very satisfactory for the purpose,

it has been very difficult and, so far as the applicant knows,impossible to secure the rooting with exposed fasteners in such a mannerthat it would give satisfactory service for more than a relatively shorttime.

Roll roofing is furnished by the manufacturers in rolls of a standardwidth and is nailed to the sheathing of the roof by various types ofnails or staples.

The completed roof is apparently very satisfactory for a short time.However, the nails or other fasteners soon become loose or even entirelyremoved, a condition known to the trade as drawing, backing out, orpcpping. This causes a great deal of dissatisfaction with this type ofroong and it is necessary for roofing manufacturers, dealers andcontractors to make many costly adjustments on roofs of this type.

The roofing trade has given the following reasons as to why roof nailscome out:

(Cl. 10S-33) Wind pressures on the under side; wind suction on the topside; the sun pops the nail; the bevel on the point moves the nail;water freezing under the head; Wet lumber getting dry after the nailsare in; dry lumber getting Wet after the nails are in; expansion andcontraction of the nail with rise and fall of temperature; moisturegetting down around the shank of the nail; weave and distortion in thesheathing and frame of the building; too large heads is thought to havesome influence, and warpage of the roofing itself.

To provide a satisfactory and permanent roof under all normal conditionshas been a very serious problem and it is essential that the fastenersor nails should not become even slightly loosened as this causes theroof to leak around the shank of the fastener, and even when a leak isnot immediately apparent any access of moisture under the head of thenail or to the fibres of the wood surrounding the nail shank will causethe nail to be forced outwardly.

When first driven the common roofing nail has enough holding power forthe purpose. However, this holding power decreases with time and thusopens the door for other forces to act.

Itis essential that this holding power should be accomplished with anail shank of such size, structure and length that the sheathing willnot be split and large slivers will not be knocked out from the underside thereby reducing the holding power by a large percentage. Also thenail head must be such as to snugly fit the inequalities of the roof andprevent access of moisture thereunder.

Yellow pine and similar sheathing, such as ordinarily used under rollroofing, one type of such sheathing being commonly known as No. 2shiplath, has been reduced in thickness as compared to old standards, bythe manufacturers, approximately 14 per cent. Roofing nails for securingroll roofing are driven into this thin sheathing. The holding power ofordinary roofing nails is materially reduced by any reduction inthickness of the sheathing.4 The problem of providing a nail fulfillingall requirements and overcoming all difculties noted herein, and assolved by the instant invention, assumes still greater importance to thetrade in View of the new problem now presented to the manufacturer ofroofing nails; that is, it is now desirable to obtain a greater holdingpower in a shorter nail, or, in other words, to provide a nail havingthe greatest effective holding characteristics to the limited amount ofsheathing thickness. This problem has been successfully solved by thepresent invention which provides a nail having, in combination withother desirable characteristics, a shank with peculiarly efficientholding power relative to the limited thickness of the sheathing inwhich it is used, and which holding power will not decrease appreciablyover extremely long periods. In fact, careful tests have shown that -theholding power actually increases.

'Ihe applicants years of experience in the manufacture of roofing nailsand the practical application of roll roofing, as well as the results ofnumerous carefully tabulated tests over long periods, have demonstratedthat to provide a satisfactory fastener of the exposed type, it isessential that all of the component parts shall be so correlated andcoordinated with special reference to form, dimension, material andiinish, that all of the nails, when used as roll roofing fasteners inthe usual type of sheathing, will remain snugly secured in position andwill prevent the access of moisture underneath the heads and to the woodfibre surrounding the shank for not less than two years even whenangularly inserted relative to the sheathing. It is also essential thatthe hole made through the roll roofing itself should snugly t the shankof the nail, 4and that the fabric should not be torn, crushed ordistorted in a manner to preventthe shank of the fastener fromcompletely closing the hole and the roofing being clamped snugly to thesheathing over the entire lower surface of the head. I

The above results have not been obtainable with any exposed fastenersheretofore available. Such fasteners show an inherent tendency to becomeloosened or otherwise unsatisfactory after exposure in normal .use forless than one year, while careful experimental use of applicants nailsunder normal and abnormal conditions has demonstrated that they willremain snugly in place and maintain the roof in satisfactory conditionfor an indefinite period very much longer than one year.

In the application of roll roofing, fasteners having rigid headsintegral with the shank have not been satisfactory because roofing nailsare often driven at an angle, and also have a tendency to tilt under thehammer thus causing an uneven clamping action of the rigid head againstthe roofing thereby allowing moisture to enter under the head. Also thistilting, or even irregularities' in the thickness of the roll roofing orin the surface of the sheathing, may cause the rigid head to `clamp`unevenly and angularly, often cutting or otherwise injuring the rollroofing.

In order to secure the maximum holding power in a roong nail of thistype the shank of the nail must be of such size and construction that itwill not unduly injure or displace the fibres of the sheathing to whichit is applied. Also it must be easily driven with a hammer in theordinary manner without splitting the wood even for a short distance, asany splitting of the wood or crushing of fibres reduces the holdingefliciency thereof. It is also desirable that the nail should not tilteasily under the hammer.

Applicants device overcomes all of the above noted objections to priordevices and it is therefore an object of the present invention toprovide a nail for fastening fabric base roll roofing to standard roofsheathing in which all of the component parts are so correlated andcoordinated with special reference to form and dimension that whenapplied in the normal manner trated in Fig. l.

.portion rectangular unusual holding `and sealing qualities areobtained.

It is a further object to provide a fastener of the characterdescribedhaving the 'above noted desirable characteristics in which Jthe holethrough the roll roofing made by the shank of the fastener will not bedistorted and will conform snugly to the cross-sectional contour of thefastener and particularly thatk part of the fastener adjacent the head,and the head will conform to the surface of the roll roofing and clampsnugly over its entire lower surface.

It is also an object to provide a fastener of the character described inwhich the threaded shank is small relative to the diameter of the headand which will easily rotate in accordance with the pitch of thethreadswhile ,driven in the sheathing under a normal blow of the hammer withouttearing or distorting the fibres of the wood suiiiciently to materiallyreduce their holding engagement with the shank over long periods.

A further object is to provide a fastener having a maximum holding powerover a long period of time, and having a minimum length of shank inwhich no part of the point or leading portion has a cross-sectionaldiameter greater than a corresponding following portion.

Further objects will be apparent from the specification and the appendedclaims.

In the drawing:

Figure 1 is a greatly enlarged side elevation of an embodiment of myinvention.

Fig. 2 is a top view of the embodiment illus- Fig. 3 is a bottom view ofthe embodiment illustrated in Fig.- 1.

Fig. 4 is a full size side elevation of the fastener illustrated in Fig.l. Fig. 5 is an enlarged cross-sectional view through the fastener and aportion of the roofing to which it is applied.

Fig. 6 is a transverse sectional view taken through the shank adjacentthe head and on a line `corresponding to line 6-6 of Fig. 5.

Fig. *'7 is a greatly enlarged sectional view through the shank andtaken on a line corresponding substantially to line T-'l of Fig. l andillustrates the slightly truncated form of the concave threads.

Fig. 8 is a side elevation of one of the nails as appliedv to a roof andillustrates the adaptability of the head when the fastener is driven ina tilted or angular position, the roll roofing and sheathing being shownin section.

Referring to the drawing in detail, the embodiment illustrated comprisesa relatively small, short threaded shank I having a comparatively largeand very nail is of malleable material and there is a definitecorrelation between the dimensions and other characteristics of the headto other parts and characteristics of the nail as will be explainedlater.

The shank is sharply pointed at 3 and this is accomplished in a mannerto provide a tapered in cross-section and having substantially flatportions 4 and sharp corners 5. The shank l is formed to provide aquadruple threadA over its entire length, the threads being preferablyconcave with slightly truncated tops 5 0f the rectangularly sharpenedpoint 3 prefer.

thin head 2 thereon. 'Ihe entire l ably form a continuation of the topsof the threads. However, in any case, no part of the point or leadingportion has a cross-sectional diameter greater than a correspondingfollowing portion, that is, the longitudinal contour of the point always'forms a reduced continuation of the longitudinal contour of the shank.

These nails are preferably formed by rst upsetting thereon a very thinhead to the required dimensions and then forming the shank of the nailto form the concave threads. The shank of the nail is very small incross-section and this method of forming the threads leaves the shankwith substantially the same cross-sectional area as the original stockfrom which it was formed. The tops of the threads may be slightlytruncated if desired, as shown in Fig. 7, and this formation togetherwith the slight roughness caused by the owing of the metal at the top ofthe truncated portion allows the wood fibres to so engage the nail as tomaterially resist any tendency to rotate outwardly due to liftingpressure, such as may be caused by the normal contraction and expansionof the sheathing or other forces such as mentioned previously.

Figs. 5 and 8 illustrate the nails in position after being driven intoposition in a roof. In

driving the nail, the point 3 rst punctures the roll roofing 8 and formsa' rectangular opening, the tops of the threads being guided into thecorners of the rectangle formed by the corners 5 of the point. As theshank enters the sheathing 9, it rotates slowly in accordance with thehigh pitch of the threads and as the threads extend completely to thehead the roofing is not torn or distorted but maintains a snug contactand conforms to the cross-sectional contour of the shank at all times.

The combined cooperative functioning of all parts of the nail duringdriving and after being completely driven permits all parts of the nailto be snugly seated and to cooperatively function after being seated ina manner to provide a maximum efficiency in holding power and in sealingagainst leakage. In other words, due to the cooperative cross sectionalrelation of all parts of the shank with a type of point which punctureswithout materially distorting or tearing, the

threads will follow the edges` cut by the point without materialdistortion of the roofing. Also, no cross section of the point and shankportion is larger than a corresponding following portion of the shank;therefore the roofing material snugly engages the shank in all drivingpositions as well as after being snugly driven in.

During the nal seating of the nail, the flexible head makes possible itsadjustment to the surface of the roofing in such a way as to compressthe roofing material very snugly around the shank and between the headand the sheathing,

thereby making a snug weatherproof engagement which is one of the firstessentials of a good fastener. The point acts somewhat as a drill anddoes not distort or displace the fibres of the wood for any appreciabledistancefrom the surface of the shank, and as the threads follow in thepath of the point, each unbroken wood fibre snugly engages acorresponding shank surface and is rigidly supported in this engagingand retaining relation by adjacent unbroken fibres.

The above-noted desirable cooperating features of the point and shank incombination with the thin exible head permits the nail to easily r otateunder a hammer blow and without undue friction on the hammer face atpoints remote from the nail shank. The nail is therefore easilycompletely seated and the roofing material, which snugly engages theshank while the nail is being driven, is further compressed around theshank and still more snugly engages the shank when the nail iscompletely seated.

The entire surface area of the shank is engaged by cooperating wood bresin a maximum holding relation and, due to the combination with theflexible head, this holding relation is maintained even when subjectedto strains incident to expansion and contraction of the roofing materialunder extreme Weather conditions.

As soon as the nail enters sufficiently to engage I the threads, thenail rotates in accordance therewith and the sharp corners' of therectangular point 3 act as drill-like cutting edges and tend to forcethe cut-off particles of wood outwardly into the pores of the woodwhereby the fibres are not materially displaced but instead yform asolid compact fibrous clamping surface engaging all parts of the shank,thus providing a fastening means which is retained in its originalholding relation for a much longer period than has been possibleheretofore.

The nails are preferably completely covered with a galvanized metalcoating which also assists in providing a surface suitable for efficientengagement of the Wood fibres therewith and prevents oxidation of theentire nail under all weather conditions. When the nail is drivenvertically into the sheathing the extreme thinness of the head, which ispreferably malleable, Will cause it to adjust itself to slightvariations in the thickness of the roll roofing or to irregularities inthe surface of the sheathing. Also the head may be easily flexed by anuneven blow of the hammer whereby friction is relieved' and the force ofthe blow may be concentrated on the shank until the head is in contactwith the roof; that is, the extreme thinness of the head and the factthat it is easily flexed permits it to give or iiex slightly under anuneven hammer blow and therefore the driving force of the blowwill beconcentrated on that part of the head directly over the shank until thenail is driven completely in when the head will conform to the surfaceof the roofing material.

These nails are usually driven very rapidly by the roofer and are veryoften somewhat angularly disposed relative to the sheathing. Heretofore,integral heads o-f fasteners for roll roofing have been rigid and anyangular displacement of the nail while being driven causes the head tocut or distort the roll roofing and also to exert its greatest clampingpressure upon the lowest portion leaving the opposite side tiltedupwardly whereby moisture enters under the head of the nail and may evenenter the sheathing around the shank. This Adestroys the efficiency ofthe nail in a short time and is particularly undesirable in cold weatheras the moisture freezes under the head of the nail and causes the nailto raise or pop and ultimately becomes entirely removed.

Iny applicants device.' as illustrated in Fig. 8

capable of conforming to the irregularities is suflciently rigid tomaintain the roll roofing securely clamped against the sheathing andover the entire lower area of the head, the materialof the nail, thefinish, and the dimensions of its component parts being so correlated asto cooperatively function in a manner to maintain the nail snugly inposition and to prevent the access of moisture thereto for aconsiderably longer period than heretofore possible. l

Satisfactory nails may-be made in which the ratio of the diameter of thethreaded shank to the head may be on the order of 1 to 5 and the headmay be of uniform thickness and substantially one twenty-fivethousandths inch thick. ratio of the thickness of the head to thediameter thereof is preferably substantially 1 to 30, Very satisfactoryresults are obtained with a nail on the. order of seven-eighths inch toone inch long and having a quadruple thread, with a diameter at the topof the threads of substantially three thirty-seconds inch, and a head onthe order of seven-sixteenths inch in diameter and twentyve thousandthsinch thick, with/the threads of a pitch to cause a substantiallythree-fourths revolution of the nail when it is driven completely in thesupport.

Modifications may be made in the embodiment herein illustrated anddescribed, and I, therefore, desire to be limited only by the prior artand the scope of the appended claims.

Having thus described my `invention, what I claim and desire to secureby Letters Patent is:

l. A nail of the character described, comprising a completely threadedpointedl shank, acomparatively large thin iiat head integral therewith,said point being of angular cross-section conforming to the number ofthreads, the sides and corners thereof forming a continuation of saidthreads, said head being sufficiently thin to conform to the surface ofa roof when the shank is driven angularly therein by the normal blow ofa hammer, the threads being of sufficiently high pitch to cause the nailto rotate in accordance therewith when the nail is driven through rollroofing and into wood sheathing, and a coating of galvanized metal overthe entire nail.

2. A nail of the character described, comprising a completely threadedpointed shank, a comparatively large thin flat head integral therewith,said point being of angular cross-section conforming to the number ofthreads, the sides and corners thereof forming a continuation of saidthreads,

lsaid head being sufficiently thin to conform tothe surface of a roofwhen the shank is driven angularly therein by the normal blow of ahammer, the threads being of suiiiciently high pitch to cause the nailto rotate in accordance therewith when the nail is driven through rollroofing and into Wood sheathing, and a coating ofgalvanized metal overthe entire nail, said threads being concave and slightly truncated.

3. In a nail of the character described for fastening roll roofing towood sheathing, the combination with a relatively small diameter shankAhaving high pitch threads over its entire length and a point forming acontinuation of said threads, of a relatively large diameter andextremely thin head integral with said shank, the dimensions of saidshank and` said head and the dimensions and pitch of the threads andtheir number and the material oi the nail being so correlated andcoordinated that a hole made thereby through roll roofing will conformto the cross- The sectional contour of the'shank, the head willbe flexedenough to yield under the blow of a hammer sufficiently to prevent unduefriction on the face of the hammer at points remote from the shank andto allow the nail to rotate in accordance with the threads withoutunduedisplacement of the wood fibres and to concentrate the force of theblow on the end of the shank, the head being suiliciently rigid toprevent distortion due to prolonged exposure to atmospheric conditions,and sufficiently deformable to conform "`to the surface of a roof whenthe shank is driven angularly therein by the normal blow of a hammer.

4. A rool roong nail of the character described comprising a shankhaving a high pitch quadruple shallow concave thread over its entirelength, a thin flat head on said shank, said nail being entirely ofmalleable material, the ratio of the diameter of said threaded shank tosaid head being on the order of 1 to 5, said head being of uniformthickness and not substantially more than one twenty-five thous'andthsinch, a point on said shank and forming a reducedcontinuation of -saidthreads, said threads being of a pitch to rotate said nail substantiallythree-fourths of a revolution.

5. A roll roong nail of the character described comprising acomparatively short shank having a high pitch quadruple thread, a flathead integral therewith, the ratio of the diameter of said shank to saidhead being on the order of 1 to 5, all of said nail being of.malleable'the nail to turn in accordance with the threads without undue frictionon the hammer and the head will be caused to conform to the surface of aroof when the shank is driven angularly therein by the normal blow of ahammer, said shank having a tapered point rectangular in cross-section,the corners of said point forming continuations of the tops of saidthreads.

6. Aroll roofing nail of the character described comprising acomparatively small shank having high pitch threads over its entirelength and arranged to rotate the nail substantially threefourths of arevolution, a comparatively large diameter head integral therewith, theratio of the diameter of said shank to said head being onthe order of 1to 5, the thickness of said head to the diameter thereof being on theorder of 1 to 30, said head and shank being integral and of malleablematerial whereby the head is easily flexed under the blow of a hammer sothat the major part of the force of the blow is concentrated on the headend of the shank, said shank having a. sharpened point.

'1. A roll roofing nail of the character described comprising acomparatively small shank having high pitch threads over its entirelength and arranged to rotate the nail substantially threefourths of arevolution, a comparatively large diameter head integral therewith, theratio of the diameter of said shank to sai-d head being on the order of1 to 5, the thickness of said head to the diameter thereof being on theorder of 1 to 30, said head and shank being integral and of malleablematerial and the head being suiiioiently thin whereby the head is easilyflexed under the blow of a hammer, said shank having a sharpened point,rectangular in cross-section,

the corners thereof forming continuations of the tops of said threads.

8. A roll roofing nail of the character described comprising a shank onthe order of from seveneighths inch to one inch long having a quadrupleconcave thread rolled therein, the diameter at the top of the threadsbeing substantially three thirty-seconds inch, and a head on said shankand integral therewith and substantially on the order ofseven-sixteenths inch in diameter and twenty-rive thousandths inchthick, all of said nail being of malleable metal, said shank having asharpened point rectangular in cross-section, the iiat surfaces of saidpoint forming continuations ofsaid threads. and the corners of saidpoint forming continuations of the tops of said threads, said threadsextending completely to said head and to a pitch to cause asubstantially three-fourths revolution of said nail when it is driveninto wood.

9. A nail of the character described for roll roong, comprising apointed and threaded shank, said shank being arranged to be cornpletelyengaged over its entire surface by wood bres when driven into wood, aflat head integral therewith, all of said nail being of malleablematerial, said head being suiciently thin over its entire area toconform to the surface of a substantially flat roof when the shank isdriven angularly therein by the normal blow of a hammer and to permitexible adjustment in accordance with irregularities' of said roofing.

10. A nail of the character described for roll roong, comprising apointed and threaded shank, said shank being arrange to be completelyengaged over its entire surface by wood bres when driven into wood, a athead integral therewith, said head being suiliciently thin to conform tothe surface of a substantially flat roof when the shank is drivenangularly therein by the normal blow of a hammer and to permit 'exibleadjustment in accordance with irregularities of said rooting, thethreads on said shank being of suiciently high pitch to cause the nailto rotate in accordance with the threads when the nail is driven intowood.

11. A nail of the character described for roll roofing, comprising apointed and threaded shank, said shank being arranged to be completelyengaged over its entire surface by wood libres when driven into wood, ailat head integral therewith, said head being suiciently thin to conformto the surface of a substantially at roof when the shank is drivenangularly therein by the normal blow of a hammer and to permit flexibleadjustment in accordance with irregularities of said roong, the threadson said shank being of suiicientlyv high pitch to cause the nail torotate in accordance with the threads when the nail is driven into wood,and acoating of galvanizing metal over the entire nail.

HAMILTON MAZE.

(Seal) CERTIFICATE 0F CORRECTION.

Parent No. 2,001,932. May 21, 193s.

HAMILTON MAZE.

A It is hereby certified that error appears in the printed specificationof the abovenumbered patent requiring correction as follows: Page 4,second column, line 2, claim 3. for "flexed" read flexible; and page 5,second column, line 3, claim 10, for "arrange" read arranged; and that.said Letters Patent should be read withthese corrections therein thatthe same may conform to the record 0f the case in the Patent Office.

` Signed and sealed this 25th day of June, A. D. 1935.

Bryan M. Battey Acting Commissioner of Patents.

